github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-23 22:52:19 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

net: dsa: microchip: implement PHY loopback configuration for KSZ8794 and KSZ8873

Browse Source 
Correct the PHY loopback bit handling in the ksz8_w_phy_bmcr and
ksz8_r_phy_bmcr functions for KSZ8794 and KSZ8873 variants in the ksz8795
driver. Previously, the code erroneously used Bit 7 of port register 0xD
for both chip variants, which is actually for LED configuration. This
update ensures the correct registers and bits are used for the PHY
loopback feature:

- For KSZ8794: Use 0xF / Bit 7.
- For KSZ8873: Use 0xD / Bit 0.

The lack of loopback support was seen on KSZ8873 system by using
"ethtool -t lanX". After this patch, the ethtool selftest will work,
but only if port is not part of a bridge.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Link: https://lore.kernel.org/r/20240124123314.734815-4-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Oleksij Rempel 2024-01-24 13:33:14 +01:00 committed by Jakub Kicinski
parent d1b7d0d85d
commit 9e62bed6e1
2 changed files with 70 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
drivers/net/dsa/microchip/ksz8795.c
View File

@ -632,6 +632,57 @@ static void ksz8_w_vlan_table(struct ksz_device *dev, u16 vid, u16 vlan)
ksz8_w_table(dev, TABLE_VLAN, addr, buf);
}
/**
* ksz879x_get_loopback - KSZ879x specific function to get loopback
* configuration status for a specific port
* @dev: Pointer to the device structure
* @port: Port number to query
* @val: Pointer to store the result
*
* This function reads the SMI registers to determine whether loopback mode
* is enabled for a specific port.
*
* Return: 0 on success, error code on failure.
*/
static int ksz879x_get_loopback(struct ksz_device *dev, u16 port,
u16 *val)
{
u8 stat3;
int ret;
ret = ksz_pread8(dev, port, REG_PORT_STATUS_3, &stat3);
if (ret)
return ret;
if (stat3 & PORT_PHY_LOOPBACK)
*val |= BMCR_LOOPBACK;
return 0;
}
/**
* ksz879x_set_loopback - KSZ879x specific function to set loopback mode for
* a specific port
* @dev: Pointer to the device structure.
* @port: Port number to modify.
* @val: Value indicating whether to enable or disable loopback mode.
*
* This function translates loopback bit of the BMCR register into the
* corresponding hardware register bit value and writes it to the SMI interface.
*
* Return: 0 on success, error code on failure.
*/
static int ksz879x_set_loopback(struct ksz_device *dev, u16 port, u16 val)
{
u8 stat3 = 0;
if (val & BMCR_LOOPBACK)
stat3 |= PORT_PHY_LOOPBACK;
return ksz_prmw8(dev, port, REG_PORT_STATUS_3, PORT_PHY_LOOPBACK,
stat3);
}
/**
* ksz8_r_phy_ctrl - Translates and reads from the SMI interface to a MIIM PHY
* Control register (Reg. 31).
@ -731,16 +782,20 @@ static int ksz8_r_phy_bmcr(struct ksz_device *dev, u16 port, u16 *val)
if (ret)
return ret;
if (restart & PORT_PHY_LOOPBACK)
*val |= BMCR_LOOPBACK;
if (ctrl & PORT_FORCE_100_MBIT)
*val |= BMCR_SPEED100;
if (ksz_is_ksz88x3(dev)) {
if (restart & KSZ8873_PORT_PHY_LOOPBACK)
*val |= BMCR_LOOPBACK;
if ((ctrl & PORT_AUTO_NEG_ENABLE))
*val |= BMCR_ANENABLE;
} else {
ret = ksz879x_get_loopback(dev, port, val);
if (ret)
return ret;
if (!(ctrl & PORT_AUTO_NEG_DISABLE))
*val |= BMCR_ANENABLE;
}
@ -1001,8 +1056,7 @@ static int ksz8_w_phy_bmcr(struct ksz_device *dev, u16 port, u16 val)
restart = 0;
restart_mask = PORT_LED_OFF | PORT_TX_DISABLE | PORT_AUTO_NEG_RESTART |
PORT_POWER_DOWN | PORT_AUTO_MDIX_DISABLE | PORT_FORCE_MDIX |
PORT_PHY_LOOPBACK;
PORT_POWER_DOWN | PORT_AUTO_MDIX_DISABLE | PORT_FORCE_MDIX;
if (val & KSZ886X_BMCR_DISABLE_LED)
restart |= PORT_LED_OFF;
@ -1022,8 +1076,16 @@ static int ksz8_w_phy_bmcr(struct ksz_device *dev, u16 port, u16 val)
if (val & KSZ886X_BMCR_FORCE_MDI)
restart |= PORT_FORCE_MDIX;
if (val & BMCR_LOOPBACK)
restart |= PORT_PHY_LOOPBACK;
if (ksz_is_ksz88x3(dev)) {
restart_mask |= KSZ8873_PORT_PHY_LOOPBACK;
if (val & BMCR_LOOPBACK)
restart |= KSZ8873_PORT_PHY_LOOPBACK;
} else {
ret = ksz879x_set_loopback(dev, port, val);
if (ret)
return ret;
}
return ksz_prmw8(dev, port, regs[P_NEG_RESTART_CTRL], restart_mask,
restart);

1
drivers/net/dsa/microchip/ksz8795_reg.h
View File

@ -265,6 +265,7 @@
#define PORT_AUTO_MDIX_DISABLE BIT(2)
#define PORT_FORCE_MDIX BIT(1)
#define PORT_MAC_LOOPBACK BIT(0)
#define KSZ8873_PORT_PHY_LOOPBACK BIT(0)
#define REG_PORT_1_STATUS_2 0x1E
#define REG_PORT_2_STATUS_2 0x2E